During the implementation of AMDF, some cross matrices are implemented by means of micro electromechanical system (MEMS), i.e., using MEMS to form relay matrix to perform wiring line switching in AMDF.
As shown in FIG. 1, an AMDF provided with MEMS mainly includes a MEMS matrix 100, device cables 200 and user cables 300, wherein the MEMS matrix 100 is connected to the device cables 200 and the user cables 300, respectively. The device cables 200 are configured to connect with the devices in communication network, and the user cables 300 are configured to connect with the user terminals in communication network. Under the control of switching control part (not shown), wiring line switching between multiply lines of the device cables 200 and the user cables 300 can be performed, so as to switch on/off the line between device and user, and effectively control the communication service in network.
When hot switching is performed in MEMS matrix, the contact point thereof may be damaged, and “agglutinate” phenomena may occur, which leads to switch unit failure in this MEMS matrix. The hot switching means the switch units in MEMS matrix switches its state when current is passing by.
In the prior art of AMDF design, there is no technical solution which can provide protection for MEMS matrix to avoid hot switching damage thereof.